1. Technical Field
The present disclosure relates generally to a relay detection apparatus and a method of operating the same, and more particularly to a relay detection apparatus and a method of operating the same which are provided to detect contact statues of relay(s) thereof.
2. Description of Related Art
Because relays have features of small size and simple control, relays are widely applied to power electronic products. Also, size and electrical specifications of relay contacts would be limited because of the small-size relay so that relay contacts have poor ability to work against inrush current.
The issue of inrush current of relays in the power electronic application is significant, that is, the greater inrush current easily causes the contact sticking, especially for the mechanical relay. Especially, the contact bounce is likely to occur when the mechanical relay is operated under the greater inrush current condition. Accordingly, the contact bounce is to cause operation malfunction, use life reduction, and even personal safety threat. In addition, due to the limitation of the relay size, most relays cannot provide the function of showing abnormal or normal contact statuses.
With the development of hybrid electric vehicles and electric vehicles, the demands of chargers for mobile vehicles are increased so that relays are more used in the charger products. Because the numbers of switching relay contacts in the chargers are frequent, the requirements of against inrush current and against contact sticking are strict. Accordingly, it is more important to detect the open/close and normal/abnormal contact statuses so as to ensure personal safety.
Accordingly, it is desirable to provide a relay detection apparatus and a method of operating the same so that the relay detection apparatus can be widely applied to different circuits in the single-phase (1Φ) AC power system and three-phase (3Φ) AC power system. In addition, the normal and/or abnormal contact statuses of the contacts of the relay can be detected out by simply detecting voltage at the contacts so that once the abnormal contact status of the contacts of the relay is detected out, the relay is interruptedly used to ensure safety of operators.